Power transmission mechanism having a reciprocatory element selectively operative in spaced operating zones



Oct. 13,1959 A. R. GROSS 2,

POWER TRANSMISSION MECHANISM HAVING A RECIPROCATORY ELEMENT SELECTIVELYOPERATIVE IN SPACED OPERATING ZONES Filed Aug. 1; 1956 5 Sheets-Sheet 1"II III menu:

Oct 1959 A. R. GROSS POWER TRANSMISSION MECHANISM HAVING A RECIPROCATORYELEMENT SELECTIVELY OPERATIVE IN SPACED OPERATING ZONES 3 Sheets-Sheet 2J INVENTOR. ArWJE 670, 07

M2 rraqyzx:

I YBY Filed Aug. 1, 1956 2,908,172 POWER TRANSMISSION MECHANISM HAVING ARECIPROCATORY I Oct. 13, 1959 A. R. GROSS ELEMENT SELECTIVELY OPERATIVEIN SPACED OPERATING ZONES Filed Aug. 1, 1956 3 Sheets-Sheet 3 UnitedStates Patent Of POWER TRANSNIISSION NLECHANISM HAVING A RECIPROCATORYELEMENT SELECTIVELY OP- ERATIVE IN SPACED OPERATING ZONES Arthur R.Gross, St. Paul, Minn.

Application August 1, 1956, Serial No. 601,410

Claims. (Cl.'74-40) My invention relates particularly to powertransmission mechanisms, and more particularly to such mechanismsemploying a reciprocatory element movable selectively in differentdirections between a neutral position and spaced operating zones.

More specifically, my present invention relates to such powertransmission mechanisms'that are particularly advantageous when used invending machines which dispense articles of merchandise responsive toinsertion of one or more coins in a receptacle therefor, a type of suchmachine being disclosed in my prior United States Letters Patent No.2,693,299 issuedNovember 2, 1954.

Vending machines for dispensing various brands of packaged goods such ascigarettes, candy bars and the like are usually provided with magazineswhich store, and from which are dispensed selectively, a plurality ofitems having different brand names, sizes, flavors, et cetera, aplurality of units of each thereof being contained in a differentmagazine, and the magazines being normally disposed in side by siderelationship within the machine. Usually, the units in each magazine arestacked one on another and, in order to provide for a substantial numberof such units and avoid refilling the magazines at unduly frequentintervals, the magazines have necessarily been of substantial height ordepth. Heretofore, machines utilizing such a plurality of magazines,each comprising two or more magazine sections, one behind the other,have employed relatively complicated mechanism for dispensing unitsfirst from one section of a magazine and then from a second section ofthe magazine when the supply of units from the first section thereof hasbeen exhausted.

The primary object of my invention is the provision of extremely simplemechanism for moving a reciprocatory element selectively in differentdirections between a neutral position and spaced operating zones.

Another object of my invention is the provision of dispensing mechanismincluding a single difierent article ejecting device for each magazine,each device being selectively operable in each of a pair of feedingzones at the delivery ends of a cooperating pair of magazine sections,whereby units of merchandise may be delivered from either section of agiven magazine by the same ejector device.

Another object of my invention is the provision of mechanism of the typeset forth including an article engaging ejector which is selectively,movable in one direction from a neutral position to cause delivery ofan article from one of a pair of spaced magazine sections, and in areverse direction from said neutral position to deliver an article ofmerchandise from the other magazine section of said pair.

Another object of my invention is the provision of novel means includinga motor and a rotary plate or disc element for imparting feeding andreturn movements to an article engaging ejector device of the above typeselectively in a pair of spaced feeding zones, and

2,908,172 Patented Oct., 13, 1959 -means againstshifting movement duringan operating cycle except at predetermined relative positions oftheplate or disc and pitman elements substantially at thebeginning or endof an operating cycle. The above and still further highly importantobjects and advantages of my invention will become app rent from thefollowing detailed specification, appended claims and attached drawings.

Referring to the drawings which illustrate the invention, and in whichlike reference characters indicate like parts throughout the severalviews:

Fig. l is a fragmentary view partly in side elevation and partly insection of the delivery mechanism of a vending and dispensing machineshowing a preferred embodiment of my invention, and taken substantiallyon the irregular line 1-1 of Fig. 3;

. Fig. 2 is an enlarged view partly in plan and partly in section takensubstantially on the-line 2-2 of Fig. 1;

Fig. 3 is a fragmentary view partly in rear elevation and partly insection taken substantially on thelline 33 of Fig. 1;

Fig. 4 is a view corresponding to Fig.2 but showing a different positionof some of the parts; 1

Fig. 5 is an enlarged fragmentary view in side elevation correspondingto a portion of Fig. 1 and showing a. different position of some of-theparts, some parts being broken away;

Fig. 6 is a fragmentary section taken of Fig. 5; Fig. 7 is an enlargedfragmentary section taken substantially on the line 77 of Fig. 5;

Fig. 8 is a wiring diagram;

Fig. 9 is a View partly in side elevation and partly in diagram showinga modified arrangement; and

Fig. 10 is a fragmentary section taken on the line 10 10 of Fig. 9.

In the preferred embodiment of my invention illustrated in Figs. 'l-8inclusive, a vending and dispensing machine is shown as comprising ahousing or cabinetl having'front and rear walls 2 and 3 respectively,end walls 4 and 5 and a bottom wall 6. Suitably mounted within thecabinet 1 are a plurality of magazines. 7 in side by side relationship,and each comprisinga front magazine section 7a and a rear magazinesection ,7b. The magazine sections 7a and 7b are open at their tops forloading and are customarily loaded each with a single row stack ofmerchandise units such as cigarette packages, the magazine sections ofeach magazine storing a m the line 6 ..6

different brand from those ofan adjacent magazine.

The merchandise units or cigarette packages are indicated at X. Thefront and rear of each magazine section 7a and 7b are defined byvertically disposedretaining flanges 8 and 9 respectively, and thebottoms thereof are defined by horizontally disposed inturned flanges10. With reference to Figs. 1 and 3 it will be'seen that the front andrear flanges 8 and 9 terminate at their lower ends in upwardly spacedrelation to the bottom forming flanges 10 a distance slightly greaterthan the thickness of each package X to permit delivery of the lowermostpackage X in each magazine section from the magazines. The lowermostpackages X in the front magazine sections 74; are adapted to be ejectedtram their respective magazine sections in a forward direction,'whereasthe lowermost packages Xin the rear magazine sections 7b are adapted tobe ejected from their respective magazine sections. in a rearwarddirection, said' ejectedpackages falling by gravity to a rearwardlyjinclinedfchute"or the like 11 which delivers the packages'tothe'-customer through an'opening 12 in the front wall2'ofthemachine,The magazines 7 including their respective sections 7'a and 7bareclearly shown and described in my prior United States patent aboveidentified? y.

(An iejeotor' carriage "1 3'ex tends transversely of the housing orcabinet land is provided at its opposite'ends with journaled rollers 14,which support the carriage 13 in a pair of channel-like rails 15,one'thereof'rigidly secured to the end wall"4," the other being weldedor otherwise rigidly securedito' avertical partition 16 in inwardlyspaced relation to the end wa1l5,{see Fig. 3. The guide rails. 15

. extend forwardly and rearwardly of the machine and i ejectors 17, onefor each of the magazines 7, each ejector 17. comprising a solenoid coilor winding 18 and an'armature 19, each armature 19 being provided at itslower end with a flange 2.0 whichnormally'rests' on a supporting lip 21of the carriage 13, With reference to Figs. 1 and 3, it will be seenthat the upper ends of the armatures 19 are normally disposed below thelowermost packages X in their respective malgazine'sections' 7a and 7b,and, that upon energi zation of 'a given solenoid 18, the'upper end "of'its. respective armature 19 moves upwardly between the lowermost.packages X in their respective magazine sections 7a and 7b. Thus, agiven armature 19 is'positioned to engage the lowermost package X in itsrespective magazine section 7a upon movement of the carriage in.its'respective magazine section 7b and move the same rearwardly to adelivery zone indicated generally at B. Upon reaching either deliveryzone Am B, the ejected packages X will fall by gravity to the chute 11and be delivered outwardly through the opening 12.

An elongated plate-like bracket 22 is pivotally secured atits oppositeends to the opposite end walls 23 of the carriage 13, as indicated 'at'24, the front edge portion of the bracket 22 resting on the heads 20ofthe'several annatures 19'. The bracket 22 carries a switch 25,the'purpose bf whichwill' hereinafter be described. The switch 25 maybeof any suitable type, but as shown is in the nature of a tube or bulbhaving spaced switch contacts therein and a small fquantity'ofmercurywhich is adapted to flow toward and away from the switch contactsto close and open the gap therebetween upon tilting of the switch inopposite directions. The carriage 13 together with the ejectors 17 andswitch carrying bracket or damper plate 22 are fully disclosed in myprior patent above identified, and further detailed showing anddescription thereof herein is believed unnecessary.

V, For the purpose of ejecting the lowermost packages X from a selectedmagazinesection 7a or 7b of a given one of said magazines. 7' I providean electrically operated motor 26'and'novel-1iukage now to be described..The

'motor 26 is; shown as being mounted on the partition 16 and ispreferably of the type having built-in speed reduction gearingterminating in an output shaft 27 on which is rigidly mounted adisc-like plate .28 to which is connected one end portion of a pitman,indicated in its entirety by the reference numeral 29. The opposite endof e m e 3. RP fQ F Y c m end t m ou e d of a back to saidneutralposition.

.:4@- relatively short crank arm 30, as indicated at 31, with theopposite end of the crank arm 30 being rigidly secured to a rockshaft 32journaled at its opposite ends insuitable bearings 32a, one of which isshown in Fig. 3; mounted on the end walls 4 and 5 of the housing 1. Apair of relatively long crank arms 33 have their lower ends rigidlysecured to the rockshaft 32, their upper ends being longitudinally.slid'ably contained in tubular members 34 one 'eachthereof beingpivotally connected to an opposite end Wall 23 of thecarriage 13'.

The disc-like plate 28 is provided with apairo fdiametricallyopposed'axially outwardly projecting portions in the form:of pins 35.-and 36 that are adapted to move in arcuate tracks 37 and 38respectively in the adjacent end portion 39 of the'pitman 29. -Ashiftable device in the is provided with a groove 41 for the receptionof a cooperating tongue portion 42 g of the pitman 29. wherebytheplate-like member 4!) is held against rotation withires'pect to thepitman '29 but longitudinally slidable with respect thereto between thearcuate tracks 37 'and38. fTheshiftable plate-like. member 40 isprovided .with a pair'of opposed recesses 43. and '44 each of which isadapted toreceive a respective pin 35 and 36 upon shifting movements eof the member" 40 in opposite directions. 'Withlrefe jence V toFigs. 2,4 and 5,'it will be seen that; when the Sh'iftmember 40 is movedto theright with respect to Figs. 2,

4;and.5, the pin. 35 will be released from the recess 43, and the-pin'36 will be received in the recess 44 whereby the shiftable connectionofthe pitman. 29 to the plate 28 will comprisethe pin 36', and the pin35 will. movellon-gitudinally through the guide channel 37 upon rotationof the plate 28. With this arrangement, when the pin 36 is receivedinthe'recess 44; and rotary movement is impartedto the plate 28, thecarriage 13 will be'caused to reciprocate between its. neutral full lineposition of Fig. l and its dotted .line' delivery position adjacent thedelivery zone A of Fig.1." When the member 40- is shifted to cause thepin 35 to be moved in the recess 43, androtary movementis'imparted tothe plate 28 inthe same direction as previously done, the pivotalconnection between theplate 28 and the pitman 29, comprises the pin 35,and the eifec tive field ofmovement of the pitman 29 is shifted in adirection longitudinally thereof. the effective field of movement iscq'uivalentto. the distancebetween the pins 35 and 36, and,'the shiftoccurring when both pins are in'registerwith' the respective recesses,the same are selectively engaged at points longitudinally spacedwithrespect to thefgeneral direction of power transmitting movement ofthepitm'an '29. With the pin 35 acting as the pivotal connection betweenthe plate 28 and the pitman .29, the carriage 13 will be moved in areverse direction from its neutral. full line position of Fig. 1 to itsdotted line position at thedelivery zone B, and

For. the purpose of imparting"'shifting movement; to

:the member .40 to cause engagement thereof with a selected one or thepins '35 and 36 I -provide a pair of spacedfsolenoid coils 45 and; 46fmounted ontheflpitman 29 by-means of'a bracket element- 47 secured tothe pitman 29 by amachinescrew or the like 48; 'An' elongated armaturerod 49 ext ends through aligned axial openings in the solenoid coils45'and 46 and is rigidly secured at one end to the outer end of a leg 50which extends laterally inwardly-through alongitudinally extended slot51 in theend portion; 39 of thepitman'29, and which is screw threaded orotherwise rigidly secured to the central portion oftheplate-likeshiftable member 40, as indicated at 52. The dispositionofthe-solenoid The extent of shift of M application is omitted.

mam

coils or 45 and 46 with respect to the armature ,49 is such that, whenthe solenoid winding 45 is energized, the shittable member 40 is movedin a direction to cause the pin 35 to be received in the recess 43.Energization of the solenoid winding 46 causes movement to be impartedto the shiftable member in the opposite direction to cause reception ofthe pin 36 'inthe recess 44 of the member 40. I

Inasmuch as the plate 28 must be properly positioned to permit theabove-described shifting movement of the member 40, I provide means fordeenergizing the motor 26 and stopping of rotation of the plate 28 whenone offthe pins' 35 or 36 is substantially in register with itsrespective recess 43 or 44. A motor cutofi switch 53 is mounted on thepartition 16 adjacent the plate 28, said switch having an operatingbutton or the like 54 which extends toward the peripheral edge of theplate 28. The peripheral edge of the plate 28 defines a cam having araised portion 55 that engages the switch button 54 to open the switch53 and deenergize the motor 26 when a disconnected one of the pins 35 or36 is in register with its cooperating recess 43 or 44 in the shiftablemember 40.

With reference to Fig. 7, it will be seen'that the solenoid coils orwindings .45 and 46 are each adapted to be connected in series withthemercury switch 25 and a source of electrical potential as exemplifiedby a battery 56, one side of which is grounded as at 57. The mercuryswitch 25 is interposed in a power lead 58'connected to the battery 56,and which extends to a movable contact element 59 of a 2-position switch60, one side of which is connected to the solenoid winding 45 by a lead61, and the other side of which is connected to the solenoid winding 46by a lead 62. The solenoid 'windings 45 and 46 are grounded to themachine asindicated at 63. The Windings'or coils 18 of the severalejectors 17 are each energizedby closing of a respective selector switch64, said switches being normally interposed in series in a lead 65 thatis connected to the power source 56. The selector circuits for theseveral ejector solenoid coils 18 are fully disclosed in my prior patentabove identified, and for the sake of brevity, detailed showing anddescription in this It will be noted, however, that energization of anyone of the selector solenoid coils 18 causes the mercury switch 25 to beclosed whereby to cause energization of a selected solenoid winding 45or 46. The switch 60 may be controlled by. any suitable means, but forthe purpose of the present example, it may be assumed that the switch 60is manually operated. The circuit of Fig. 7 further includes a pair ofcontrol relays 66 and 67, the former of which includes a coil or winding68 and a normally open switch 69, and the latter of which comprises acoil or winding 70 and a normally open switch 71. The relay coils 68 and70 are connected in parallel with the solenoid coils 45 and 46respectively, by means of respective leads 72 and 73 connected to theleads 61 and 62 respectively, and a common ground connection 74. Themotor 26 is energized by the mercury switch 25 through a portion of alead 75 which extends to the holding and cutoff switch 53, and fromthence to the motor 26 to hold the same energized when the switch 53 isclosed. A pair of leads 76 and 77 are connected at one end to the lead75, and at their other ends are connected to one side of a respectiverelay switch 69 and 71. The opposite sides of the switches 69 and 71 areconnected to the motor 26 by a common lead 78 and a portion of the lead75, the motor being grounded as indicated at 79.

Assuming that the movable switch contact 59 of the switch 60 ispositioned to energize the solenoid coil 45, closing of one of theselector switches 64 will cause closing of the mercuryswitch 25 byupward swinging movement of the bracket or damper plate 22 and energizethe relay winding 68 to close the switches 69 fine the last mentionedcircle.

and 70, whereby to energize the dispensing motor 26. Energization of themotor 26 causes the disc-like plate 28 to rotate to initiate ejection ofa package X,fron 1'the selected magazine section 7a. As fully disclosedin my prior patent, above identified, movement of the ejector carriage13 to its dotted line position of Fig. 1 at the dispensing zone A causesthe mercury switch 25 to be opened to deenergize the coil 68 of therelay 66 and opening of the switches 69 and 70 thereof. However, by thetime the switch 25 is opened, the holding and cutofl switch 53 has beenclosed and the motor 26 continues to operate until the switch 53 isreopened by the cam 55. p

Inasmuch as energization of the shifting solenoids 45 and 46 iscontrolled by the mercury switch 25 as, well as the switch 60, shiftingof the shiftable member 40 to disengage one pin and engage the other canbe accomplished only when the switch 25 is closed and when the pins 35and 36 are aligned. or in register with their respective recesses 43 and44 of the shiftable member 40. It will be noted that, during rotation ofthe plate 28, the engaged or operative one of the 'pins 35 or 36 exertsrotating force on one side or the other of its respective recess, thustending to move the shiftable member 40 out of engagement with theengaged pin during part of'an operating cycle. Also during a part ofsaid cycle the load of the carriage 13 is transferred by the linkagetherebetween and the plate 28 to the member 40, tending to shift themember 40 out of engagement with the engaged or operative pin. As aboveindicated, the member 48 is of general elliptical shape, having opposedarcuate edges 80 and 81 each extending from opposite sides of adjacentrecesses 43 and 44. The arcuate edge 80 is concentric with the pin 36when the pin 36 is seated in its cooperating recess 44, whereas thearcuate edge 81 is concentric with the pin 35 when the same is'seated inits cooperating recess 43. The radii of the arcuate edges are such that,when one of the pins is seated in its respective recess, the other pintravels in close proximity to the opposite arcuate edge of the member 40during a part of the rotary movement of the plate 28. For the purpose offurther preventing shifting movement of the member 40 during rotation ofthe plate 28, I provide guide means in the nature of spaced arcuateflanges 82, 83, 84-, and projecting generally axially or laterally fromthe adjacent face of the plate 28, and a guide pin 86 screw-threadedinto the plate 28. The guide flanges 82 and 83 define arcs of a circleconcentric with the pin 36, and the guide flanges 84 and 85 define arcsof a circle concentric with the pin 35, the guide pin 86 and pin 36cooperate with the flanges 84 and 85 to de- Further, the pin 35cooperates with the guide flanges 82 and 83 to define the firstmentioned circle. When the pin 35 is seated in the recess 43, thearcuate edge portions 81 are adapted to be engaged by the flanges 84 and85 and the pin 36 and the guide pin 86, which cooperate to confine themember 40 against shifting movement when both pins 35 and 36 are not inregister with their respective recesses 43 and 44. In like manner, whenthe pin 36 is seated in its respective recess 44 the arcuate edgeportions 30 are adapted to be engaged by the pin 35 and guide flanges 82and 83 which cooperate to confine the member 40 against shiftingmovement during the operational cycle of the machine. Preferably, thepins 35 and 36 are rigidly secured to the plate element 28, and

the several guide flanges 82-85 are integrally :formed with the plateelement 28. For this reason, the guide pin 86 is removable to permitshifting movement of the member 40 during such time that one or theother of the pins is out of register with its cooperating recess in themember 40, whereby to permit assembly or dis assembly of the pitman29-from the plate 28 in a direction transversely of the axis of theplate 28.

In the modified form of the invention illustrated in.

acce e-2 Eig.- 9, the disc-like crank, pitman, shiftable member and,platena rrnialre identical to those illustrated in Figs. and parrylikereference numeralswith prime marks addedl "Thus, the disc-like plate isindicated at 28', the pitman 259 being provided with a shiftable member40, and being connected at its outer end to the crank arm 30" asindicated at 31'. In this modification, a bar or shaft- 87 is connectedat one end to the leg 50' lwhich'extends laterally outwardly from theshiftable member 40 The shaft 87 is longitudinally slidably carried byone end of a latch bracket 88 mounted on the pitman 29'. The shaft 87 isprovided with a laterally outwardly projecting latchbolt 89 that isreceivable selectively'in one of a pair of spaced recesses 90 and 91'inthe latch bracket 88, to lock the shaft. 87 and shiftable member 40' ina selected position with respect to thepins carried by the disc-likeplate 28'.

-An'operating' circuit for the motor 26' which is connected" to theplate 28 bythe drive shaft 27', is shown as comprising the source ofpotential 56', the mercury switch. 25f,-a relay'92 comprising a windingor coil 93 and a normally open switch 94 and a pair of switches 95 and96 operated by a control arm 97 engageable with the cam 55. of the plate28. The switch cooperates with the mercury switch 25 to controloperation of the relay coil 93, and the switch 96 is a holding switchsimilar to'the holding switch 53 to maintain the motor 26 energizeduntilthe control arm 97 is engaged by .the cam portion 55' todeenergizethe motor 26 when the s'hiftable member 40' and both pins onthe plate 28' are in relative positions permitting shifting of themember 40 As shown, the mercury switch 25' relay coil 93 and switch 95are serially connected in a lead 98 connected at one end' to the battery56' and grounded asindicated at. 99. 'The battery 56 is also grounded asindicated at 57 to complete the circuit through said re-tnierc'ury'switch 25" is controlled in the same manner as the switch 25,showing of the selector switches and solenoids thereof being omitted,

My novel disc-like plate and pitman arrangement has been shown anddescribed as a power transmission mechanism for vending and dispensingmachines as an example of the use for which the same is adapted.However, the device is capable of application to various mapin and theother of saidrecesses into engagement its eooperatingip in when thereces ses andipinsiare in' registration. to shift the field of movement ofsaid pit; man in a'direction longitudinally thereof, and means torrestraining said pinengaging member against .shifting movements wheneither of said recesses is out of Wg stration with the cooperating pin,said means comprising spaced arcuate confining guide flanges on saidplaterem gageable with the arcuate edges'of said pin engaging memberduring rotation of the plate and inoperatively Y -pin removably securedto said plate 'on'the circumferentially extended arc of said relativelyshort flange in circumferentially spaced relation thereto, wherebyremoval of said guide pinpermits shifting movements to.

be imparted to saidpin engagingmember when the disengagedpin is outofregistration with therespective,

recess'and also out of engagement with the cooperating t arcuatetsurface,of said pin engaging mernber toenchines requiring the peculiarmovements achieved by instant structure. It will be further noted that,if desired, the pitman 29 may be utilized as the driving member from asuitable pair of spaced prime movers, not shown, to

rotary movement to the disc-like plate 28. While I have shown anddescribed a commercial embodiment of my novel device, and a singlemodification thereof, it will be understood that the same is capable offurther modification without departure'from'the spirit and scope of theinvention as defined in the claims.

What I claim is: I 1. In a power transmission mechanism, a powerdrivenrotatable plate and a cooperating pitman,-a pair of diametricallyopposed pins on said plate, a generally elliptical pin engaging member,means mounting said member on said pitman for shifting 'movementslongitudinally thereof, opposed arcuate edges of said memberdefiningopposed recessesueach receiving a difiterent one of saidlpinsruponshifting movements of said member in opposite' directionsrelativeto said pitman, mechanism for imparting movement to said memberto move one of said recesses out of, engagement, withrthe cooperatingableflsaid pitman and pin engaging member to here:

moved from'en'gagement with said plate in a, direction transverselyofthe of said plate. 3. ,The, structure. defined in claim 1 in which saidmechanism 'forimparting movement to the pin engaging memberincludes'solenoid means mounted on .said pitman and cooperating armaturestructure operativcly .coupledto said .pin engaging member and movablein oppositefdirectionsby said solenoidmeans. V

-4. In a power transmission mechanism, a plate element and a:cooperating pitman element movable relative to the plate element, a pairof pivot pins mounted on one of the said elements, said pivot pins beingfixed in spaced relationship to each other relative to the directionofmovement of said pitman element, a pin engaging mem: ber, means mountingsaid pin-engaging member on the other said element for shifting movementthereon relative .to thepivot pins to a plurality of operativepositions, said pin engaging member having a pair of pin-receivingrecesses in spaced relationship to each other relative to t thedirection of movement of said pitmanelement, one of saidpins beingreceived in one of said recessesupon shifting movementof the pinengagingmember to each of the operative positions, and mechanism forimpar ting shifting movement to said pin engaging member betweencesseseach for receiving a different one of the pins upon shiftingmovement of the pin engaging memberlin opposite directions relative tothe pitman, and mechanism for ur'g ing one of the recesses of .the pinengaging membenout of engagement with one; of the pins and the otherrecess into engagementwiththe other pin to shift the effective field-ofmovement of'said pitman between spaced opera;

tivejzones. e a

-6. In a power transmission mechanism, a plate element and a cooperatingpitman element movable relative to the plate element, ,apair of pivotpins" mounted on one of the said elements, said pivot pins being fixedin spaced relationship to each other relative to the direction ofmovement of said pitman element, a pin engaging member movably mountedon the other said element for shifting movement relative to the pivotpins to a plurality of operative positions, said pin engaging memberhaving a pair of recesses in spaced relationship to each other relativeto the direction of movement of said pitman element, one of said pinsbeing received in one of said recesses upon shifting movement of the pinengaging member to each of the operative positions, mechanism for urgingsaid pin engaging member between the operative positions to move one ofsaid recesses out of engagement with the cooperating pin and the otherrecess into engagement with the other pin to shift the eifective fieldof movement of said pitman element between a neutral zone and spacedoperative zones, and guide means on the said one element for engagingthe pin engaging member to enable the shifting movement of the memberonly when the pins are positioned to be engaged by the recesses.

7. In a power transmission mechanism, a power driven rotatable disc anda cooperating pitman, a pair of pins positioned in diametrically opposedrelationship to each other on said disc, a pin engaging member mountedon said pitman for shifting movement thereon generally longitudinallythereof, said pin engaging member having a pair of spaced recesses eachfor receiving a-difierent one of the pins upon shifting movement of thepin engaging member in opposite directions relative to the pitman,mechanism for imparting shifting movements to said pin engaging memberto move one of the recesses of the pin engaging member out of engagementwith one of the pins and the other recess into engagement with the otherpin to shift the effective field of movement of said pitman betweenspaced operative zones, and guide means on said disc for engaging thepin engaging member to confine said member against shifting movementduring rotation of the disc and enabling such shifting movement onlywhen the pins are positioned to be selectively engaged by the recessesof the pin engaging member.

8. In a power transmission mechanism, a plate element and a cooperatingpitman element movable relative to the plate element, a pair of pivotpins mounted on the plate element in spaced relationship to each otherrelative to the direction of movement of the pitman element, a shiftabledevice movably mounted on the pitman element for shifting movementrelative to the pivot pins to a plurality of operative positions toselectively engage the pivot pins, and mechanism for moving theshiftable device out of engagement with one of the pivot pins in oneselected operative position and into engagement with the other pivot pinin another operative position to shift the effective field of the pitmanelement between spaced operative zones.

9. The structure defined in claim 8, in further combination with meanson the plate element for engaging the shiftable device to enable theshifting movement of the shiftable device only when the pivot pins arepositioned to be selectively engaged by the shiftable device.

10. In a power transmission mechanism, a rotatable plate element and alinkage operatively coupled to the plate element, said linkage includinga pitman movable relative to the plate element, a shiftable elementmounted on said pitman for movements relative thereto and selectivelyengaging spaced elements mounted on said plate clement at pointslongitudinally spaced with respect to the direction of powertransmitting movement of said pitman, a pin connected to said shiftableelement and mounted on said pitman in spaced generally parallel relationthereto for shifting movements in opposite directions longitudinallythereof, and a latch bolt projecting laterally outwardly of said pin,said pitman defining latch bolt receiving recesses for locking said pinand shiftable element at opposite ends of the shifting movement thereof.

References Cited in the file of this patent UNITED STATES PATENTS313,481 Dodd Mar. 10, 1885 545,407 Judd et al Aug. 27, 1895 892,688Schrum July 7, 1908 904,764 Drecoll Nov. 24, 1908 1,119,637 Roberts Dec.1, 1914 1,137,757 Headson May 4, 1915 1,779,981 Nickerson Oct. 28, 19302,057,770 Du Grenier Oct. 20, 1936 2,146,728 Fleischer Feb. 14, 19392,197,634 Du Grenier Apr. 16, 1940 2,280,218 Cook Apr. 21, 19422,693,299 Gross Nov. 2, 19 54

